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Circularly polarized luminescence (CPL) plays a crucial role in the fields of optical display and information technology. The pursuit of high dissymmetry factors (g_lum) and fluorescence quantum yields in CPL materials remains challenging due to inherent trade-offs. In this work, molecular imprinting technology is employed to develop novel CPL-active polymer films based entirely on achiral fluorene-based polymers, achieving an enhanced g_lum value exceeding 4.2 × 10^-2 alongside high quantum yields. These chiral molecularly imprinted polymer films (MIPF) are synthesized via a systematic three-step process: co-assembly with limonene and a porphyrin derivative (TBPP), interchain crosslinking, and subsequent removal of small molecules. During this process, limonene acts as the chiral inducer, while TBPP serves dual roles as both the chiral enhancer and imprinted molecule. The elimination of TBPP creates chiral sites for various fluorescent molecules, facilitating full-color CPL emission. The chiral MIPF exhibits stable CPL performance even after multiple cycles of post-assembly and removal. Furthermore, these films can function as interfacial microreactors, enabling in situ chemical reactions that dynamically regulate CPL signals. Additionally, chiral self-organization within achiral azobenzene polymer films can also be achieved using MIPF, serving as intense chiral light sources.

The synthesis of porphyrinoid-based low-dimensional polymers has recently attracted considerable interest in view of their intriguing electronic, optical, and catalytic properties. Here, this is introduced by the surface-assisted synthesis of two carbaporphyrinoid-based polymers of increasing dimensionality under ultrahigh-vacuum conditions. The structural and electronic characterization of the resulting polymers has been performed by scanning tunneling and non-contact atomic force microscopies, complemented by theoretical modeling. First, a carbon-carbon coupling between dicarbahemiporphyrazine precursors is achieved by thermal activation of their isopropyl substituents via a [3+3] cycloaromatization, giving rise to one-dimensional (1D) polymers. Second, the same precursor is functionalized with chlorine atoms to complement the [3+3] cycloaromatization with orthogonal dehalogenation and homocoupling, affording two-dimensional (2D) molecular nanostructures. In addition, both low-dimensional free-base porphyrinoid-based polymers are exposed to an atomic flux of cobalt atoms, giving rise to cobalt-metalated macrocycles, with the metal atoms coordinated only to the two pyrrolic nitrogens, in contrast to the typical four-fold coordination that occurs inside tetrapyrroles. This on-surface protocol renders atomically precise covalently-linked porphyrinoid polymers and provides promising model systems toward the exploration of low-coordinated metals with utility in diverse technological areas.

Liquid metals (LMs) illustrate a fantastic future. Thus, great endeavors are made to earn a comprehensive understanding of this fluid and carve it into a niche. Herein, by revisiting the combination of Ga-based LMs and aluminum (Al), a new phenomenon, namely the disintegration of LM films on encountering water, is identified. Deviating from previous investigations where the LM generally took the form of bulk puddles, the LM-Al slurry is spread as thin films here. In this case, Al debris embedded in the LM matrix hydrolyzes and therefore can exert disjoining pressure strong enough to split the thin film into countless tiny LM droplets. Based on this mechanism, transient circuits independent of substrate decomposition are realized. Furthermore, taking advantage of the portfolio strategy of pure LM and the LM-Al slurry, novel concepts of flood warning and information storage and encryption are demonstrated. Integrating these functions all in one demonstrates the versatility of the disintegration of thin LM films engendered by Al corrosion, which provides a scientific insight into ephemeral art and makes the Ga─Al combination more illuminating.